THERE were at least nineteen strong earthquakes in the world during March, and at least seven during April. The strongest shock during March was probably that of March 3 from an epicentre near lat. 18° N., long. 119° E. off the north-west coast of Luzon, Philippine Islands. It gave ground amplitudes of 160 µ at Kew. The second strongest was on March 1, from an epicentre near lat. 3° S., long. 130-5° E., off the west coast of New Guinea. This gave ground amplitudes of 80 µ at Kew. The deepest shock during March occurred on March 23 from an epicentre near lat. 51° N., long. 155° E., off the southern coast of Kamchatka. The depth of focus was between 200 and 250 km. The only great shock on land was on March 27, when a severe earthquake shook the city of Sucre in Bolivia, causing considerable damage to property, including the cathedral, plunging the city into darkness and cutting off communications with the rest of Bolivia ; only three casualties have been reported. An earth tremor on March 16 was felt at Lourdes, Argeles and Bagnères ; but no damage is reported. There were no great earthquakes on land during April. The greatest earthquake during April was that on April 21 from an epicentre near lat. 19° N., long. 69·5° W., off the north-east coast of the Dominican Republic, and the deepest (200 km.) was on April 12 from an epicentre near lat. 14° N., long. 90-5° W., off the coast of Guatemala. Reports for these months have been received from the International Bureau at Strasbourg, the Jesuit Seismological Association, the U.S. Coast and Geodetic Survey and the following individual observatories : Cleveland (Ohio), Beograd, De Bilt, Durham, Kew, Stuttgart, Toledo, Uccle, Zurich and the Swiss stations.